Cryopreservation the mammalian embryo enables conservation of hereditary resources of specific systems and kinds. It is effective for maintaining animals standing on the brink of ruin. It is useful for infertility treatment.
As a method for cryopreservation mammalian embryos, as disclosed in patent document 1 (Japanese Patent Application Laid-Open Publication No. 2000-189155), there is proposed a method for cryopreservation mammalian embryos that mammalian embryos or ova are bonded to the inner surface of the cryopreservation container such as the sterilized frozen straw, frozen vial or frozen tube by using a vitrifying liquid in an amount minimum and enough to enclose the mammalian embryos or the ova therewith. The cryopreservation container is sealed and rapidly cooled by bringing the cryopreservation container into contact with liquid nitrogen. In the thawing method, the cryopreservation container stored in the above method is taken out of the liquid nitrogen and one end thereof is opened. A diluted liquid of 33 to 39 degrees C. is injected directly into the container to thaw the mammalian embryos or the ova and dilute the vitrifying liquid. This method eliminates a possibility that the mammalian embryos or the ova are infected with a disease through viruses or bacteria and is capable of storing them at a high survival rate and thawing them and diluting the vitrifying liquid.
But the operation of bonding eggs such as embryos and ova to the inner surface of the cryopreservation container such as the frozen straw, the frozen vial or the frozen tube by using the vitrifying liquid in an amount minimum and enough to enclose them therewith is not easy.